1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
|
/*
Please use git log for copyright holder and year information
This file is part of libbash.
libbash is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 2 of the License, or
(at your option) any later version.
libbash is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with libbash. If not, see <http://www.gnu.org/licenses/>.
*/
///
/// \file bash_condition.cpp
/// \brief implementation for Bash Conditional Expressions
///
#include "core/bash_condition.h"
#include <ctime>
#include <boost/lexical_cast.hpp>
#include <sys/stat.h>
#include <unistd.h>
#include "core/bash_ast.h"
#include "core/exceptions.h"
#include "core/interpreter.h"
namespace
{
bool test_file_stat(char op, const std::string& path)
{
struct stat info;
int status = 0;
// symbol link use lstat so we need to separate this.
if(op == 'L' || op == 'h')
return lstat(path.c_str(), &info) == 0 && S_ISLNK(info.st_mode);
status = stat(path.c_str(), &info);
if(status != 0 || access(path.c_str(), F_OK))
return false;
switch(op)
{
case 'a':
case 'e':
return true;
case 'b':
return S_ISBLK(info.st_mode);
case 'c':
return S_ISCHR(info.st_mode);
case 'd':
return S_ISDIR(info.st_mode);
case 'f':
return S_ISREG(info.st_mode);
case 'g':
return S_ISGID & info.st_mode;
case 'k':
return S_ISVTX & info.st_mode;
case 'p':
return S_ISFIFO(info.st_mode);
case 'r':
return access(path.c_str(), R_OK) == 0;
case 's':
return info.st_size > 0;
case 'u':
return S_ISUID & info.st_mode;
case 'w':
return access(path.c_str(), W_OK) == 0;
case 'x':
return access(path.c_str(), X_OK) == 0;
case 'O':
return geteuid() == info.st_uid;
case 'G':
return getegid() == info.st_gid;
case 'S':
return S_ISSOCK(info.st_mode);
case 'N':
return info.st_mtime >= info.st_atime;
default:
throw libbash::illegal_argument_exception(std::string("Unrecognized test operator -") + op);
}
}
}
bool internal::test_unary(char op, const std::string& target)
{
switch(op)
{
case 'z':
return target.empty();
case 'n':
return !target.empty();
case 'o':
throw libbash::unsupported_exception("Shell option test is not supported");
case 't':
try
{
int fd = boost::lexical_cast<int>(target);
return isatty(fd);
}
catch(boost::bad_lexical_cast& e)
{
return false;
}
default:
return test_file_stat(op, target);
}
}
namespace
{
bool file_comp(char op,
const std::string& lhs,
const std::string& rhs)
{
struct stat lst, rst;
int lstatus, rstatus;
lstatus = stat(lhs.c_str(), &lst);
rstatus = stat(rhs.c_str(), &rst);
if(op == 'e' && (lstatus < 0 || rstatus < 0))
return false;
switch(op)
{
case 'n':
/* -nt */
return ((lstatus > rstatus) || (lstatus == 0 && lst.st_mtime > rst.st_mtime));
case 'o':
/* -ot */
return ((lstatus < rstatus) || (rstatus == 0 && lst.st_mtime < rst.st_mtime));
case 'e':
/* -ef */
return (lst.st_dev == rst.st_dev && lst.st_ino == rst.st_ino);
default:
throw libbash::illegal_argument_exception(std::string("Unrecognized option for file test ") + op);
}
}
}
bool internal::test_binary(const std::string& op,
const std::string& lhs,
const std::string& rhs,
interpreter& walker)
{
if(op.size() != 2)
throw libbash::illegal_argument_exception("Unrecognized operator " + op);
try
{
if(op == "nt")
return file_comp('n', lhs, rhs);
else if(op == "ot")
return file_comp('o', lhs, rhs);
else if(op == "ef")
return file_comp('e', lhs, rhs);
// We do not support arithmetic expressions inside keyword test for now.
// So the operands can only be raw integers.
else if(op == "eq")
return walker.eval_arithmetic(lhs) == walker.eval_arithmetic(rhs);
else if(op == "ne")
return walker.eval_arithmetic(lhs) != walker.eval_arithmetic(rhs);
else if(op == "lt")
return walker.eval_arithmetic(lhs) < walker.eval_arithmetic(rhs);
else if(op == "le")
return walker.eval_arithmetic(lhs) <= walker.eval_arithmetic(rhs);
else if(op == "gt")
return walker.eval_arithmetic(lhs) > walker.eval_arithmetic(rhs);
else if(op == "ge")
return walker.eval_arithmetic(lhs) >= walker.eval_arithmetic(rhs);
else
throw libbash::illegal_argument_exception("Unrecognized operator " + op);
}
catch(boost::bad_lexical_cast& e)
{
return false;
}
}
|
GitWeb